Microbial Communities in the Upper Respiratory Tract of Patients with Asthma and Chronic Obstructive Pulmonary Disease

Abstract

Respiratory infections are well-known triggers of chronic respiratory diseases. Recently, culture-independent tools have indicated that lower airway microbiota may contribute to pathophysiologic processes associated with asthma and chronic obstructive pulmonary disease (COPD). However, the relationship between upper airway microbiota and chronic respiratory diseases remains unclear. This study was undertaken to define differences of microbiota in the oropharynx of asthma and COPD patients relative to those in healthy individuals. To account for the qualitative and quantitative diversity of the 16S rRNA gene in the oropharynx, the microbiomes of 18 asthma patients, 17 COPD patients, and 12 normal individuals were assessed using a high-throughput next-generation sequencing analysis. In the 259,572 total sequence reads, α and β diversity measurements and a generalized linear model revealed that the oropharynx microbiota are diverse, but no significant differences were observed between asthma and COPD patients. Pseudomonas spp. of Proteobacteria and Lactobacillus spp. of Firmicutes were highly abundant in asthma and COPD. By contrast, Streptococcus, Veillonella, Prevotella, and Neisseria of Bacteroidetes dominated in the healthy oropharynx. These findings are consistent with previous studies conducted in the lower airways and suggest that oropharyngeal airway microbiota are important for understanding the relationships between the various parts of the respiratory tract with regard to bacterial colonization and comprehensive assessment of asthma and COPD.

The role of the local microbial ecosystem in respiratory health and disease

“…Metagenomic sequencing has demonstrated that the healthy adult oropharynx is colonized with pathobionts such as Streptococcus, Haemophilus and Neisseria spp. and the Gramnegative, anaerobic putative commensal genera Veillonella, Prevotella, Leptotrichia and Fusobacterium [3,[70][71][72][73][74]. A recent study in children showed a similar oropharyngeal microbiome composition to that observed in adults, with enrichment of, most notably, Neisseria, Granulicatella, Prevotella, Porphyromonas, Fusobacteriaceae and certain Prevotella spp.…”

Streptococcus pneumoniae Colonization Disrupts the Microbial Community within the Upper Respiratory Tract of Aging Mice

“…Young mice maintained high levels of Proteobacteria throughout colonization with S. pneumoniae. Although the role of Proteobacteria within the URT still remains unclear, some studies have shown its presence to be quite common within this niche (38).…”

Comparison Study of Oropharyngeal Microbiota in Case of Bronchial Asthma and Chronic Obstructive Pulmonary Disease in Different Severity Levels

“…Однако культуральные методики не дают полной картины микробиоты человека, так как при их помощи можно выявить лишь около 10-40% бактерий, населяю-щих человеческий организм [5]. Появление новых куль-туронезависимых методик оценки микробиоты человека, основанных на детекции генов бактериальной 16S рРНК, позволило сделать огромный скачок в идентификации видового состава бактериальной флоры [6].…”

“…Так, орофарингельная микрофлора больных БА ха-рактеризуется более высокой представленностью бакте-рий, относящихся к типу Bacteroidetes, которые являются значимым компонентом микробиоты здоровых индиви-дов [5]. Более выраженное присутствие P. melaninogenica является благоприятным фактором, благодаря способ-ности данной бактерии несколько снижать активность воспаления в дыхательных путях, в частности путем мо-дулирования иммунного ответа, а также препятствовать колонизации патогенных протеобактерий [14].…”